1. Field
The disclosed and claimed concept relates generally to testing equipment and methodologies and, more particularly, to a method of automatically verifying a position of a sensor during performance of an evaluation procedure on an object under test.
2. Related Art
Periodic maintenance and evaluation are required for numerous types of equipment. Certain types of equipment have very large numbers of components that are very similar to one another and the testing of which is likewise similar to one another, and thus it has been known to automate certain testing functions with robots and the like.
In the evaluation of certain types of equipment, it is necessary to evaluate a degree of degradation or change over a period of time of the equipment. In such circumstances, it is typically necessary to compare the results of current testing with the results of prior testing. In so doing, it is necessary to retrieve historical data, compare it with current data, and evaluate any changes that have occurred in order to characterize the degradation of each such component of an object under test. However, it is also necessary to ensure that the proper historical data is being compared with the proper current data, and it is therefore also necessary to periodically verify that the position of the testing equipment is correct, meaning that the component which is being evaluated by sensors for comparison with historical data is the correct component and not, say, an adjacent, different component.
It thus has been known to rely upon one or more Uniquely Identified Locations (UILs) on an object under test to determine a current position of a sensor, for instance, of a testing apparatus. Conventional UILs on a steam generator in a nuclear power plant might include a number of locations on the steam generator such as plugged tubes, support rods, painted tubes, and the like. That is, the position of the sensor at any given time is determined in respect to one or more UILs on the object under test. It therefore has also been known to periodically (during the course of an evaluation procedure) robotically move the sensor to one of the UILs in order to confirm that the position from which the sensor was moved to the UIL is, in fact, the position where the system believed it to be. While such methodologies have been generally effective for their intended purposes, they have not been without limitation.
An example of an environment in which an object under test has numerous similar components that must be individually evaluated is in the case of a steam generator of a nuclear power plant. Such a steam generator might include ten thousand or more tubes that are in fluid communication with a primary loop of the nuclear power plant, and each of the tubes must be periodically evaluated for degradation in order to avoid the potential for leakage of primary coolant into a secondary loop. At various times, such testing is performed by causing a robotically controlled eddy current sensor to be passed through the various tubes of the steam generator, and the signal from the eddy current sensor is compared with a historical signal that is stored in a storage in order to enable an evaluation to be made of possible degradation of the tube. In order to ensure that the retrieved historical data is being compared with the proper current data, the robot moves the probe at least once every four hours, say, to a UIL to ensure that the position of the sensor immediately prior to its movement to the UIL was the position where the system believed that the sensor has been situated. However, such movement of the sensor to a UIL and then back to a component such as a tube has been time consuming and wasteful of resources. It thus would be desired to provide an improved system that overcomes these and other shortcomings associated with the known art.